Essential hypertension is the leading contributory cause of death in the U.S. At present, the treatment of choice is with antihypertensive agents. Many of the antihypertensive drugs have undesirable side effects (impotence, gastric distress, diarrhea and psychic disturbance). New methods of treatment without these side effects would be welcome. Evidence suggests that behavioral techniques (relaxation training, biofeedback) are efficacious in lowering blood pressures without the expense and undesirable side effects of drugs. The promised potential of these techniques is as yet unfulfilled because most of the experiments have utilized normotensive subjects, relevant control groups were missing, statistical rather than clinical significance was demonstrated and generalization of the results outside of the laboratory was not forthcoming. The proposed experiments are unique in determining blood pressures and heart rates of patients outside of the laboratory automatically while they are going about their normal daily routines. Forty-eight mild essential hypertensives will wear a blood pressure cuff and automatic recording equipment once per week for two weeks (8 hours each day) to get an estimate of systolic and diastolic blood pressure outside of the lab while doing their daily routine. Then 16 patients with be taught Bensonian relaxation training which they will practice once a day for eight weeks (20 min. each); 16 patients will practice uninstructed relaxation once a day for 8 weeks; 16 patients will receive biofeedback for lowering frontalis EMG levels. In the treatment phase all patients will come in once per week for 8 weeks to practice relaxation, feedback or uninstructed rest in the laboratory and to have their EMGs and pressures recorded while doing so. Patients will wear the blood pressure monitor twice after 8 weeks of treatment to get an estimate of how they are doing. Patients will come back for a 3 month follow-up where they will wear the blood pressure device twice over two weeks. The study will provide data on blood pressures outside of the lab setting, whether a Bensonian relaxation training is more efficacious than biofeedback or uninstructed rest and whether the training generalizes outside of the laboratory. Finally it will provide data on the durability of the effect.